That’s why the National Science Foundation awarded Gallant a $1.5 million grant in 2017 to better understand electric fish genetics and firmly establish the fish as model organisms. “They’ve become this evolutionary laboratory that allows us to better characterize and understand ion channels.” “Electric fish are masters of messing with what’s usually a very highly constrained biophysical system,” Gallant said. Understanding how and why those adaptations work allows researchers to discover and explore general biological principles. Credit: Mary Swartz/Johann Eberhart/University of Texas at Austin.įish have much more flexibility thanks to their duplicate genes, allowing electric fish to do some extraordinary things with their ion channels, such as evolving an electric organ. The zebrafish is not an electric fish, but, like humans and most other vertebrates, it has sodium channels in its muscles, which are fluorescing green in this image. In fact, there are conditions including epilepsy that can have their roots in mutations or other deviations to the channels. In humans and other vertebrates, there’s very little wiggle room when it comes to sodium channels and similar proteins called ion channels. “That’s why some of the oldest textbooks in the field have engravings of electric eels on them.” “Electric fish are really important biomedical models,” Gallant said. “So the next step in terms of human health would be to examine this region in databases of human genes to see how much variation there is in healthy normal people and whether some deletions or mutations in this region could lead to a lowered expression of sodium channels, which might result in disease.” “This control region is in most vertebrates, including humans,” Zakon said. And the implications go far beyond the evolution of electric fish. The researchers found that, in electric fish, this control region is either altered or entirely missing. The team discovered a short section of DNA in the sodium channel gene that controls whether the gene is expressed in any given cell. The new research is helping show exactly how it happened. ![]() Electric fish turned off one copy of the sodium channel gene in muscle, turned it on in other cells and voila: a new organ was born. All fish have duplicate versions of the same gene that produces tiny muscle motors, called sodium channels. They’re related to the better-known strongly electric fish, such as electric eels, that can generate enough power to stun prey or zap predators.Įvolution took advantage of a quirk of fish genetics to develop electric organs. ![]() Weakly electric fish are fish that use weak electric signals in a manner akin to bird songs, to communicate with other electric fish and share important information, including their sex and species. The pintail knifefish is a weakly electric fish that helped researchers uncover clues about the evolutionary history of the electric organ.
0 Comments
Leave a Reply. |